The field of this invention relates to a sound absorbing apparatus to diminish the level of sound emitted from a specific source and more particularly to a sound attenuator for a gas flow duct to diminish the sound that is produced by the apparatus that is producing the air movement through the duct.
The moving of a gas through a duct system is exceedingly common within industry. A typical gas would be air. A common form of an apparatus to move air through the duct system would be a fan or blower. The basic construction of a blower would comprise a shaft upon which are mounted fan blades. Rotation of the blades results in air movement forward of the blades. This air movement is directed by a duct to a particular location.
Because of the physical size of the blowers, it is common that a substantial amount of noise will be generated in the operation of the blower. To any individual working in close proximity to the blower, the noise generated not only can be annoying, but actually can be damaging to one's ears after a period of time.
It has been found that, like the gas itself, the noise is directed downstream of the duct. It has been known in the past to insert some type of device within the duct to mute sound within the duct, yet permit the air to flow through the duct in a substantially unrestricted manner. There is a need to constantly improve on such devices to decrease as much as possible the sound within the duct. The structure of the present invention is directed to such a device that improves upon the efficiency of prior art sound absorbing apparatuses.